Health monitoring unit with hypotension predictive graphical user interface (GUI)

ABSTRACT

A health monitoring unit includes a hardware processor, a memory, a display, and a graphical user interface (GUI) stored in the memory. The GUI is executed by the processor to provide a selection screen enabling a user to select parameters for viewing on the display from among health parameters of a living subject being tracked by the health monitoring unit. The GUI also presents a main screen showing the parameters selected by the user, the main screen including an icon for communicating a hypotension probability index (HPI) status of the living subject. In addition, the GUI overlays an alarm screen as a pop-up on the display if the HPI of the living subject satisfies a predetermined risk criteria, and enables the user to access an HPI diagnostic screen showing values for a subset of the health parameters identified as predictive of a future hypotension event for the living subject.

BACKGROUND

Hypotension, or low blood pressure, can be a harbinger of seriousmedical complications, and even mortality, for patients undergoingsurgery and those acutely or critically ill patients receiving treatmentin an intensive care unit (ICU). The dangers associated with theoccurrence of hypotension in a patient are due both to the potentialinjury caused by the hypotension itself and to the many seriousunderlying medical disorders that the occurrence of hypotension maysignify.

In and of itself, hypotension in surgical patients or critically illpatients is a serious medical condition. For example, in the operatingroom (OR) setting, hypotension during surgery is associated withincreased mortality and organ injury. Even short durations of extremehypotension during surgery are associated with acute kidney injury andmyocardial injury. Among critically ill patients, in-hospital mortalitymay be nearly doubled for patients experiencing hypotension afteremergency intubation. For surgical patients and seriously ill patientsalike, hypotension, if not corrected, can impair organ perfusion,resulting in irreversible ischemic damage, neurological deficit,cardiomyopathy, and renal impairment.

In addition to posing serious risks to surgical patients and criticallyill patients in its own right, hypotension can be a symptom of one ormore other serious underlying medical conditions. Examples of underlyingconditions for which hypotension may serve as an acute symptom includesepsis, myocardial infarction, cardiac arrhythmia, pulmonary embolism,hemorrhage, dehydration, anaphylaxis, acute reaction to medication,hypovolemia, insufficient cardiac output, and vasodilatory shock. Due toits association with such a variety of serious medical conditions,hypotension is relatively common, and is often seen as one of the firstsigns of patient deterioration in the OR and ICU. For instance,hypotension is seen in up to approximately thirty-three percent ofsurgeries overall, and up to eighty-five percent in high risk surgeries.Among ICU patients, hypotension occurs in from approximately twenty-fourpercent to approximately eighty-five percent of all patients, with theeighty-five percent occurrence being seen among critically ill patients.

Conventional patient monitoring for hypotension in the OR and ICUsettings can include continuous or periodic blood pressure measurement.However, such monitoring, whether continuous or periodic, typicallyprovides no more than a real-time assessment. As a result, hypotensionin a surgical patient or critically ill patient is usually detected onlyafter it begins to occur, so that remedial measures and interventionscannot be initiated until the patient has entered a hypotensive state.Although, as noted above, extreme hypotension can have potentiallydevastating medical consequences quite quickly, even relatively mildlevels of hypotension can herald or precipitate cardiac arrest inpatients with limited cardiac reserve.

In view of the frequency with which hypotension is observed to occur inthe OR and ICU settings, and due to the serious and sometimes immediatemedical consequences that can result when it does occurs, a solutionenabling prediction of a future hypotension event, before itsoccurrence, is highly desirable.

SUMMARY

There are provided exemplary implementations of a health monitoring unitwith a hypotension predictive graphical user interface (GUI), andmethods for use by such a health monitoring unit, substantially as shownin and/or described in connection with at least one of the figures, andas set forth more completely in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a diagram of an exemplary health monitoring unit with ahypotension predictive graphical user interface (GUI), according to oneimplementation;

FIG. 2A shows a more detailed exemplary implementation of thehypotension predictive GUI shown in FIG. 1;

FIG. 2B shows a trace of an arterial pressure waveform includingexemplary indicia corresponding to the probability of future hypotensionin a living subject;

FIG. 3 is a flowchart presenting an exemplary method for use by a healthmonitoring unit with a hypotension predictive GUI;

FIG. 4A shows an exemplary selection screen of a hypotension predictiveGUI provided on a display of a health monitoring unit, according to oneimplementation;

FIG. 4B shows an exemplary main screen of a hypotension predictive GUIpresented on a display of a health monitoring unit, according to oneimplementation;

FIG. 4C shows an exemplary alarm screen of a hypotension predictive GUIoverlaid as a pop-up on a display of a health monitoring unit, accordingto one implementation;

FIG. 4D shows an exemplary hypotension probability index (HPI)diagnostic screen of a hypotension predictive GUI provided on a displayof a health monitoring unit, according to one implementation;

FIG. 5A shows an exemplary selection screen of a hypotension predictiveGUI provided on a display of a health monitoring unit, according toanother implementation; and

FIG. 5B shows an exemplary main screen of a hypotension predictive GUIpresented on a display of a health monitoring unit, according to anotherimplementation.

DETAILED DESCRIPTION

The following description contains specific information pertaining toimplementations in the present disclosure. One skilled in the art willrecognize that the present disclosure may be implemented in a mannerdifferent from that specifically discussed herein. The drawings in thepresent application and their accompanying detailed description aredirected to merely exemplary implementations. Unless noted otherwise,like or corresponding elements among the figures may be indicated bylike or corresponding reference numerals. Moreover, the drawings andillustrations in the present application are generally not to scale, andare not intended to correspond to actual relative dimensions.

The present application discloses a health monitoring unit with ahypotension predictive graphical user interface (GUI). The healthmonitoring unit converts data received from a hemodynamic sensor todigital hemodynamic data of a living subject and obtains healthparameters that are often highly predictive of future hypotension forthe living subject from the digital hemodynamic data. The healthmonitoring unit utilizes some or all of the health parameters todetermine a risk score or hypotension probability index (hereinafter“HPI”) corresponding to the probability of a future hypotension eventfor the living subject.

The hypotension predictive GUI of the health monitoring unit provides ahealth care worker such as a doctor or nurse (hereinafter “user”) withpowerful options for monitoring and evaluating the probability of afuture hypotension event for the living subject. By providing aselection screen on a display of the health monitoring unit, thehypotension predictive GUI disclosed by the present application enablesthe user to select parameters for viewing on the display from among thehealth parameters of the living subject being tracked by the healthmonitoring unit. By presenting a main screen on the display thatincludes an icon for communicating the HPI status of the living subjectregardless of the parameters selected by the user, the hypotensionpredictive GUI disclosed by the present application renders the HPIstatus of the living subject continuously observable by the user.

In addition, by overlaying an alarm screen as a pop-up on the healthmonitoring unit display if the HPI of the living subject satisfies apredetermined risk criteria, the hypotension predictive GUI disclosed bythe present application ensures that a timely warning of a futurehypotension event is provided to the user. Moreover, by enabling theuser to access an HPI diagnostic screen showing values for a subset ofthe health parameters identified as predictive of the future hypotensionevent, the hypotension predictive GUI disclosed by the presentapplication provides detailed diagnostic information allowing the userto identify a most probable cause of the future hypotension event aswell as possible medical interventions for its prevention.

FIG. 1 shows a diagram of an exemplary system for performing healthmonitoring. System 100 includes health monitoring unit 102, which may bean integrated health monitoring unit, for example, and hemodynamicsensor 142 coupled to health monitoring unit 102. As shown in FIG. 1,health monitoring unit 102 includes system processor 104, implemented asa hardware processor, system memory 106, analog-to-digital converter(ADC) 108, display 120, and sensory alarm 124. As further shown in FIG.1, system memory 106 of health monitoring unit 102 stores hypotensionpredictive GUI 130 and hypotension prediction software code 110including health parameters 112.

It is noted that hypotension predictive GUI 130 is shown in FIG. 1 asbeing provided on display 120, as well as being stored in system memory106 to indicate that hypotension predictive GUI 130 is executed byhardware processor 104 to provide an interactive user interface viadisplay 120 of health monitoring unit 102. Also shown in FIG. 1 isdigital hemodynamic data 126 generated by ADC 108 from signal 144received from hemodynamic sensor 142.

Health monitoring unit 102 may be implemented within a patient careenvironment such as an intensive care unit (ICU) or operating room (OR),for example. As shown in FIG. 1, in addition to health monitoring unit102 and hemodynamic sensor 142, the patient care environment includespatient 140 (hereinafter “living subject 140”), and healthcare worker146 (hereinafter “user 146”) trained to utilize health monitoring unit102. As will be discussed in greater detail below, hypotensionpredictive GUI 130 is configured to receive inputs 128 from user 146,and to invoke sensory alarm 124 if the HPI for living subject 140satisfies a predetermined risk criteria.

Hemodynamic sensor 142 is shown in an exemplary implementation in FIG.1, and is attached to living subject 140. It is noted that hemodynamicsensor 142 may be a non-invasive or minimally invasive sensor attachedto living subject 140. In one implementation, as represented in FIG. 1,hemodynamic sensor 142 may be attached non-invasively at an extremity ofliving subject 140, such as a wrist or finger of living subject 140.Although not explicitly shown in FIG. 1, in other implementations,hemodynamic sensor 142 may be attached non-invasively at an ankle or toeof living subject 140. Signal 144 received by health monitoring unit 102from hemodynamic sensor 142 may include signals corresponding to thearterial pressure of living subject 140. Health monitoring unit 102 andhemodynamic sensor 142 may be configured such that signal 144 may bereceived by health monitoring unit 102 wirelessly, or via a wiredconnection with hemodynamic sensor 142.

According to the exemplary implementation shown in FIG. 1, systemprocessor 104 is configured to utilize ADC 108 to convert signal 144 todigital hemodynamic data 126. System processor 104 is further configuredto execute hypotension prediction software code 110 to transform digitalhemodynamic data 126 to health parameters 112. System processor 104 isfurther configured to execute hypotension prediction software code 110to determine the HPI for living subject 140 based on health parameters112. In addition, system processor 104 is configured to executehypotension predictive GUI 130 to invoke sensory alarm 124 if the HPIsatisfies a predetermined risk criteria.

For example, system processor 104 may be configured to executehypotension predictive GUI 130 to overlay an alarm screen as a pop-up ondisplay 120 if the HPI of living subject 140 satisfies a predeterminedrisk criteria. In such an implementation, overlaying the alarm screen asa pop-up on display 120 may cause sensory alarm 124 to be invoked. Thus,hypotension predictive GUI 130 and/or sensory alarm 124 may be used byhealth monitoring unit 102 to warn of a hypotension event for livingsubject 140 predicted to occur approximately one to five minutes in thefuture, or up to approximately thirty minutes in the future.

In various implementations, sensory alarm 124 may be implemented as oneor more of a visual alarm, an audible alarm, and a haptic alarm. Forexample, when implemented to provide a visual alarm, sensory alarm 124may be invoked as flashing and/or colored graphics shown by hypotensionpredictive GUI 130 on display 120, and/or may include displaying the HPIvia hypotension predictive GUI 130 on display 120. When implemented toprovide an audible alarm, sensory alarm 124 may be invoked as anysuitable warning sound, such as a siren or repeated tone. Moreover, whenimplemented to provide a haptic alarm, sensory alarm 124 may causehealth monitoring unit 102 to vibrate or otherwise deliver a physicalimpulse perceptible to user 146.

It is noted that the HPI for living subject 140 is determined based onhealth parameters 112, which in turn are derived from signal 144 ofliving subject 140 received from hemodynamic sensor 142. Consequently,according to the inventive concepts disclosed by the presentapplication, system processor 104 of health monitoring unit 102 isconfigured to execute hypotension prediction software code 110 todetermine the HPI for living subject 140 without comparison with datacorresponding to hypotension in other living subjects. In other words,hypotension prediction software code 110 determines the HPI for livingsubject 140 based on health parameters 112, without reference to ahypotension patient database storing information regarding hypotensionin patients other than living subject 140.

Referring to FIG. 2A, FIG. 2A shows a more detailed exemplaryimplementation of hypotension predictive GUI 130, in FIG. 1. In otherwords, hypotension predictive GUI 230, in FIG. 2A corresponds in generalto hypotension predictive GUI 130, in FIG. 1, and each of hypotensionpredictive GUI 130 and hypotension predictive GUI 230 may share any ofthe characteristics attributed to either of hypotension predictive GUI130 and hypotension predictive GUI 230 in the present application.

As shown in FIG. 2A, hypotension predictive GUI 230 includes severalmodules for facilitating interaction by a user, such as user 146, inFIG. 1, with hypotension predictive GUI 230. Among the modules includedin hypotension predictive GUI 230 are selection module 232, presentationmodule 234, overlay module 236, and user access module 238. It is notedthat the functionality of selection module 232, presentation module 234,overlay module 236, and user access module 238 will be described belowwith reference to flowchart 360, in FIG. 3.

Continuing to FIG. 2B, diagram 200 in FIG. 2B shows a trace of arterialpressure waveform 250 including exemplary indicia for determining theHPI for living subject 140. Arterial pressure waveform 250, which may bea central arterial pressure waveform of living subject 140, for example,may correspond to digital hemodynamic data 126, converted by ADC 108 ofhealth monitoring unit 102 from signal 144 received from hemodynamicsensor 142.

As shown in FIG. 2B, arterial pressure waveform 250 includes exemplaryindicia 252, 254, 256, and 258, corresponding respectively to the startof a heartbeat, the maximum systolic pressure marking the end ofsystolic rise, the presence of the dicrotic notch marking the end ofsystolic decay, and the diastole of the heartbeat of living subject 140.Also shown by diagram 200 is exemplary slope 248 of arterial pressurewaveform 250. The indicia extracted from arterial pressure waveform 250,such as exemplary slope 248 and exemplary indicia 252, 254, 256, and258, may be transformed by hypotension prediction software code 110 tohealth parameters 112.

In addition to the indicia 252, 254, 256, and 258 of arterial pressurewaveform 250 per se, the behavior of arterial pressure waveform 250during the intervals between those indicia may also be used as indiciafor determining the HPI for living subject 140. For example, theinterval between the start of the heartbeat at indicia 252 and themaximum systolic pressure at indicia 254 marks the duration of thesystolic rise (hereinafter “systolic rise 252-254”). The systolic decayof arterial pressure waveform 250 is marked by the interval between themaximum systolic pressure at indicia 254 and the dicrotic notch atindicia 256 (hereinafter “systolic decay 254-256”). Together, systolicrise 252-254 and systolic decay 254-256 mark the entire systolic phase(hereinafter “systolic phase 252-256”), while the interval between thedicrotic notch at indicia 256 and the diastole at indicia 258 mark thediastolic phase of arterial pressure waveform 250 (hereinafter“diastolic phase 256-258”).

Also of potential diagnostic interest is the behavior of arterialpressure waveform 250 in the interval from the maximum systolic pressureat indicia 254 to the diastole at indicia 258 (hereinafter “interval254-258”), as well as the behavior of arterial pressure waveform 250from the start of the heartbeat at indicia 252 to the diastole atindicia 258 (hereinafter “heartbeat interval 252-258”). The behavior ofarterial pressure waveform 250 during intervals: 1) systolic rise252-254, 2) systolic decay 254-256, 3) systolic phase 252-256, 4)diastolic phase 256-258, 5) interval 254-258, and 6) heartbeat interval252-258 may be determined by measuring the area under the curve ofarterial pressure waveform 250 and the standard deviation of arterialpressure waveform 250 in each of those intervals, for example. Therespective areas and standard deviations measured for intervals 1, 2, 3,4, 5, and 6 above may serve as additional indicia for determining theHPI for living subject 140.

Example implementations of the present inventive concepts will befurther described below with reference to FIG. 3, FIGS. 4A, 4B, 4C, and4D (hereinafter “FIGS. 4A-4D”), and FIGS. 5A and 5B. FIG. 3 presentsflowchart 360 outlining an exemplary method for use by health monitoringunit 102 including hypotension predictive GUI 130/230. FIGS. 4A-4D showuser interaction screens provided by hypotension predictive GUI 130/230,executed by system processor 104, through use of respective selectionmodule 232, presentation module 234, overlay module 236, and user accessmodule 238, according to one implementation. FIGS. 5A and 5B show userinteraction screens provided by hypotension predictive GUI 130/230,executed by system processor 104, through use of respective selectionmodule 232, presentation module 234, overlay module 236, and user accessmodule 238, according to another implementation.

It is noted that the various user interaction screens shown by FIGS.4A-4D are depicted as being provided by hypotension predictive GUI 430via display 420, while the user interaction screens shown by FIGS. 5Aand 5B are depicted as being provided by hypotension predictive GUI 530via display 520. Hypotension predictive GUI 430/530, in FIGS. 4A-4D, 5A,and 5B corresponds in general to hypotension predictive GUI 130/230, inFIG. 1/2B. That is to say, each of hypotension predictive GUI130/230/430/530 may share any of the characteristics attributed to anyother hypotension predictive GUI 130/230/430/530 in the presentapplication.

In addition, display 420/520, in FIGS. 4A-4D, 5A, and 5B corresponds ingeneral to display 120, in FIG. 1. Thus, each of display 120/420/520 mayshare any of the characteristics attributed to any other display120/420/520 in the present application. Display 120/420/520 may take theform of a liquid crystal display (LCD), a light-emitting diode (LED)display, an organic light-emitting diode (OLED) display, or anothersuitable display screen that performs a physical transformation ofsignals to light.

Referring to FIGS. 1, 2A, 3, and 4A in combination, flowchart 360 beginswith providing selection screen 462 enabling user 146 to selectparameters 472 and 484 for viewing on display 120/420 from among healthparameters 112/412 of living subject 140 being tracked by healthmonitoring unit 102 (action 362). Selection screen 462 is provided ondisplay 120/420 of health monitoring unit 102 by hypotension predictiveGUI 130/230/430, executed by system processor 104, and through use ofselection module 232.

As shown by FIG. 4A, selection screen 462 of hypotension predictive GUI130/230/430 enables user 146 to select from among health parameters112/412 including cardiac output (CO) 472, stroke volume (SV) 474,stroke volume variation (SVV) 476, diastolic pressure (DIA) 477, pulserate (PR) 478, stroke volume index (SVI) 480, systemic vascularresistance (SVR) 482, mean arterial pressure (MAP) 414, and HPI 484. Inaddition, health parameters 112/412 being tracked by health monitoringunit 102 include systemic vascular resistance index (SVRI), cardiacindex (CI), and systolic pressure (SYS). It is noted that healthparameters 112/412 being tracked by health monitoring unit 102 mayfurther include additional parameters not represented on selectionscreen 462. Also shown in FIG. 4A is exit button 486 enabling user 146to close selection screen 462 of hypotension predictive GUI 130/230/430.

According to the exemplary implementation shown by FIG. 4A, hypotensionpredictive GUI 130/230/430 is implemented as a touch screen userinterface. However, in other implementations, hypotension predictive GUI130/230/430 may be configured to receive inputs 128 from user 146 via akeyboard, via another type of input device, such as a mouse or pressurepad, or as voice commands spoken by user 146, for example.

As shown by the shadowing of parameters 476, 480, and 484, user 146 hasselected CO 472 and HPI 484 for viewing on display 120/420 of healthmonitoring unit 102 from among health parameters 112/412 being trackedby health monitoring unit 102.

Referring to FIG. 4B in combination with FIGS. 1, 2A, and 3, flowchart360 continues with presenting main screen 464 of hypotension predictiveGUI 130/230/430 showing parameters CO 472 and HPI 484 selected by user146 from selection screen 462 (action 364). It is noted that HPI 484 isdepicted visually on interactive screens of hypotension predictive GUI130/230/330 other than selection screen 462 as “P(↓BP)” and is shown onmain screen 464 as P(↓BP) 484. It is further noted that the acronym HPIand its symbolic representation as P(↓BP) may be used interchangeablyhereinafter. Main screen 464 is provided on display 120/420 of healthmonitoring unit 102 by hypotension predictive GUI 130/230/430, executedby system processor 104, and through use of presentation module 234.

As shown by FIG. 4B, main screen 464 of hypotension predictive GUI130/230/430 shows P(↓BP) 484 numerically and as a trace displayed as afunction of time. The trace as a function of time and numerical valueshown for each of CO 472 and P(↓BP) 484, as well as for blood pressure(BP) 488, which may be included as a default parameter from among healthparameters 112/412, may be shown continuously on main screen 464, andmay be updated periodically, such as every approximately twenty seconds,for example.

According to the implementation shown by FIG. 4B, P(↓BP) 484 is shown asa number between zero and one hundred (0-100) corresponding to theprobability that living subject 140 will experience a hypotension event.That is to say, a P(↓BP) near zero indicates that a hypotension event ishighly unlikely, while a P(↓BP) near 100 indicates a high probability ofan impending hypotension event. The trace and numerical value of P(↓BP)484 may exhibit a color corresponding in general to the probability of afuture hypotension event for living subject 140. For example, arelatively low P(↓BP), such as a P(↓BP) of less than or equal to 50 maycause the trace and/or numerical value of P(↓BP) 484 to appear green onmain screen 464. However, a higher P(↓BP), such as a P(↓BP) between 50and 85, for example, may cause the trace and/or numerical value ofP(↓BP) 484 to appear yellow, while a high P(↓BP), such as a P(↓BP) over85, may cause the trace and/or numerical value of P(↓BP) 484 to turnred.

In addition to the features described above, main screen 464 ofhypotension predictive GUI 130/230/430 provides shortcut button 490enabling user 146 direct access to an HPI diagnostic screen, describedbelow, including additional data for evaluating the probability andlikely cause of a future hypotension event for living subject 140.

Referring to FIG. 4C in combination with FIGS. 1, 2A, and 3, flowchart360 continues with overlaying alarm screen 466 as a pop-up on display120/420 of health monitoring unit 102 if P(↓BP) 484 of living subject140 satisfies a predetermined risk criteria (action 366). Overlay ofalarm screen 466 on display 120/420 of health monitoring unit 102 isperformed by hypotension predictive GUI 130/230/430, executed by systemprocessor 104, and through use of overlay module 236.

The predetermined risk criteria may be based on the value of P(↓BP) 484,on the trend of P(↓BP) 484 over a time interval, or both. For example,having P(↓BP) 484 exceed a threshold of 85, for instance, may causealarm screen 466 to pop-up substantially immediately. Alternatively, orin addition, a lower risk score may cause alarm screen 466 to pop-up ifit exceeds a predetermined threshold over the entirety of apredetermined time period.

Thus, for example, while having P(↓BP) 484 equal to 85 or more may causealarm screen 466 to pop-up substantially immediately, having P(↓BP) 484at or above 80 may cause alarm screen 466 to pop-up after severalseconds at that level, such as ten to thirty seconds in which P(↓BP) 484is continuously between 80 and 85, for example. By analogy, a stilllower value of P(↓BP) 484 may cause alarm screen 466 to pop-up if thatP(↓BP) value is maintained continuously for one or more minutes. In yetanother implementation, P(↓BP) 484 may cause alarm screen 466 to pop-upif it meets or exceeds a predetermined value a predetermined number oftimes over a predetermined time period. For example, having P(↓BP) 484exceed 75 three times over a five minute interval may cause alarm screen466 to pop-up.

Once alarm screen 466 does pop-up, alarm screen 466 overlays display120/420 persistently until an acknowledgement input is received fromuser 146 via hypotension predictive GUI 130/230/430. For example, user146 may either simply acknowledge the alarm by selecting acknowledge bar416, or may request more information by selecting more information bar418. Selection of acknowledge bar 416 by user 146 may cause alarm screen466 to disappear, while selection of more information bar 418 mayprovide user 146 with direct access to the HPI diagnostic screen,described below, which includes additional data for evaluating theprobability and likely cause of a future hypotension event for livingsubject 140. Thus, it is noted that the HPI diagnostic screen describedbelow is accessible to user 146 from main screen 464 via shortcut button490, as well as from alarm screen 466 via more information bar 418.

In some implementations, overlaying alarm screen 466 as a pop-up ondisplay 120/420 causes sensory alarm 124/424 to be invoked. As notedabove by reference to FIG. 1, sensory alarm 124/424 may be implementedas one or more of a visual alarm, an audible alarm, and a haptic alarm.For example, when implemented to provide a visual alarm, sensory alarm124/424 may be invoked as flashing and/or colored graphics shown byhypotension predictive GUI 130/230/430 on display 120/420, and/or mayinclude displaying P(↓BP) 484 via hypotension predictive GUI 130/230/430on display 120/420. When implemented to provide an audible alarm,sensory alarm 124/424 may be invoked as any suitable warning sound, suchas a siren or repeated tone. Moreover, when implemented to provide ahaptic alarm, sensory alarm 124/424 may cause health monitoring unit 102to vibrate or otherwise deliver a physical impulse perceptible to user146.

Referring to FIG. 4D in combination with FIGS. 1, 2A, and 3, flowchart360 can conclude with enabling user 146 to access HPI diagnostic screen468 showing a subset of health parameters 112/412 identified ashypotension risk indicators predictive of a future hypotension event forliving subject 140 (action 368). Access to HPI diagnostic screen 468 isenabled by hypotension predictive GUI 130/230/430, executed by systemprocessor 104, and through use of user access module 238.

As shown in FIG. 4D, in addition to the numerical values for CO 472 andP(↓BP) 484 shown on main screen 464 of hypotension predictive GUI130/230/430, HPI diagnostic screen 468 of hypotension predictive GUI130/230/430 shows numerical values and variations for hypotension riskindicators identified as predictive of a future hypotension event.According to the exemplary implementation shown by FIG. 4D, thehypotension risk indicators include MAP 114/414, DIA 477, SVR 482, SV474, PR 478, SVV 476, arterial elastance (E_(a)) 494, and left ventriclecontractility (dP/dt) 496.

The hypotension risk indicators shown as predictive health parameters onHPI diagnostic screen 468 can enable user 146 to identify a mostprobable cause of the future hypotension event for living subject 140.For example, HPI diagnostic screen 468 provided by hypotensionpredictive GUI 130/230/430 may enable user 146 to identify one or moreof poor vascular tone, low blood volume, or reduced cardiaccontractility, to name a few exemplary causes, as a most probable causeof a predicted future hypotension event.

Furthermore, in some implementations, the predictive health parametersshown on HPI diagnostic screen 468 can enable user 146 to determine amedical intervention for preventing the future hypotension event forliving subject 140. For example, values and variations for MAP 414, CO472, SVV 476, and SV 474 are highlighted in green on HPI diagnosticscreen 468, indicating that those health parameters are low risk withrespect to the probability of a hypotension event for living subject140. Values and variations for PR 478 and SVR 482 are highlighted inyellow on HPI diagnostic screen 468, indicating that those healthparameters are moderate risk with respect to the probability of ahypotension event for living subject 140.

It is noted that the predictive health parameters shown on HPIdiagnostic screen 468 are drawn on HPI diagnostic screen 468 as a treewith MAP 414 at the top, and CO 472 and SVR 482 being linked to oneanother below MAP 414 by a branched connection coming from MAP 414. PR478 and SV 474 are similarly linked to one another below CO 472 by abranched connection coming from CO 472. In addition, SVV 476, dP/dt 496,and E_(a) 494 are linked to one another below SV 474 by a branchedconnection coming from SV 474. Based on the information shown by HPIdiagnostic screen 468, i.e., P(↓BP) 484 at a relatively safe level of35, a hypotension event is not imminent for living subject 140.

Moving to FIGS. 5A and 5B, FIGS. 5A and 5B show an implementation ofhypotension predictive GUI 130/230/530 in which the main screen ofhypotension predictive GUI 130/230/530 displays health parameters 112using a speedometer type display format. As shown by FIG. 5A, selectionscreen 562 of hypotension predictive GUI 130/230/530 enables user 146 toselect from among the same health parameters 112/412 shown in FIG. 4A,i.e., CO 572, SV 574, SVV 576, DIA 577, PR 578, SVI 580, SVR 582, MAP514, and HPI 584, as well as SVRI, CI, and SYS. Thus health parameters512 correspond respectively to health parameters 112/412 and may shareany of the characteristics attributed to those corresponding featuresabove. Also shown in FIG. 5A is exit button 586 enabling user 546 toclose selection screen 562 of hypotension predictive GUI 130/230/530.

According to the exemplary implementation shown by FIG. 5A, hypotensionpredictive GUI 130/230/530 is implemented as a touch screen userinterface. However, in other implementations, hypotension predictive GUI130/230/530 may be configured to receive inputs 128 from user 146 via akeyboard, via another type of input device, such as a mouse or pressurepad, or as voice commands spoken by user 146, for example. As shown bythe shadowing of parameters 576, 578, and 580, user 146 has selected SVV576, MAP 514, and HPI 584 for viewing on display 120/520 of healthmonitoring unit 102 from among health parameters 112/412/512 beingtracked by health monitoring unit 102.

Referring to FIG. 5B, FIG. 5B shows main screen 564 of hypotensionpredictive GUI 130/230/530 displaying parameters SVV 576, MAP 514, andP(↓BP) 584 selected by user 146 from selection screen 562. As shown byFIG. 5B, main screen 564 of hypotension predictive GUI 130/230/430/530also provides shortcut button 590 enabling user 146 direct access to anHPI diagnostic screen corresponding to HP diagnostic screen 468, in FIG.4D, and including additional data for evaluating the probability andlikely cause of a future hypotension event for living subject 140.

As further shown by FIG. 5B, the health parameters shown on main screen564 of hypotension predictive GUI 130/230/530 are displayed by referenceto color coded risk zones. For example, in the value reported for P(↓BP)584 is shown to fall in a relatively safe green zone. The value for MAP514 is shown to fall in a yellow zone, indicating that the value of MAP514 presents moderate risk with respect to the probability of ahypotension event for living subject 140. By contrast to healthparameters highlighted in green or yellow, the value of SVV 576 is shownto have increased into a red zone, indicating that SVV 25 is a high riskhealth parameter with respect to the probability of a hypotension eventfor living subject 140.

In the event that P(↓BP) 584 or one or more others of health parameters112/412/512 satisfies a predetermined risk criteria, as described aboveby reference to FIG. 4C, alarm screen 466 may overlay 120/420/520 as apop-up. Overlay of alarm screen 466 on display 120/420/520 of healthmonitoring unit 102 is performed by hypotension predictive GUI130/230/430, executed by system processor 104, and through use ofoverlay module 236.

As discussed above, once alarm screen 466 does pop-up, alarm screen 466overlays display 120/420/520 persistently until an acknowledgement inputis received from user 146 via hypotension predictive GUI130/230/430/530. For example, user 146 may either simply acknowledge thealarm by selecting acknowledge bar 416, or may request more informationby selecting more information bar 418. Selection of acknowledge bar 416by user 146 may cause alarm screen 466 to disappear, while selection ofmore information bar 418 may provide user 146 with direct access to HPIdiagnostic screen 468, described above.

Thus, the hypotension predictive GUI of the health monitoring unitdisclosed by the present application provides a user with powerfuloptions for monitoring and evaluating the probability of a futurehypotension event for a living subject. By providing a selection screenon a display of the health monitoring unit, the hypotension predictiveGUI disclosed by the present application enables the user to selectparameters for viewing on the display from among the health parametersof the living subject being tracked by the health monitoring unit. Bypresenting a main screen on the display that includes an icon forcommunicating the HPI status of the living subject regardless of theparameters selected by the user, the hypotension predictive GUIdisclosed by the present application renders the HPI status of theliving subject continuously observable by the user.

In addition, by overlaying an alarm screen as a pop-up on the healthmonitoring unit display if the HPI of the living subject satisfies apredetermined risk criteria, the hypotension predictive GUI disclosed bythe present application ensures that a timely warning of a futurehypotension event is provided to the user. Moreover, by enabling theuser to access an HPI diagnostic screen showing values for a subset ofthe health parameters identified as predictive of the future hypotensionevent, the hypotension predictive GUI disclosed by the presentapplication provides detailed diagnostic information allowing the userto identify a most probable cause of the future hypotension event aswell as possible medical interventions for its prevention.

From the above description it is manifest that various techniques can beused for implementing the concepts described in the present applicationwithout departing from the scope of those concepts. Moreover, while theconcepts have been described with specific reference to certainimplementations, a person of ordinary skill in the art would recognizethat changes can be made in form and detail without departing from thescope of those concepts. As such, the described implementations are tobe considered in all respects as illustrative and not restrictive. Itshould also be understood that the present application is not limited tothe particular implementations described herein, but manyrearrangements, modifications, and substitutions are possible withoutdeparting from the scope of the present disclosure.

What is claimed is:
 1. A system for monitoring of arterial pressure of apatient and providing a warning to medical personnel of a predictedfuture hypotension event, the system comprising: a hemodynamic sensorthat produces an analog hemodynamic sensor signal representative of anarterial pressure waveform of the patient; an analog-to-digitalconverter that converts the analog hemodynamic sensor signal to digitalhemodynamic data; a system memory that stores hypotension predictionsoftware code and a graphical user interface; a display; and a hardwareprocessor that is configured to: execute the hypotension predictionsoftware code to: derive, from the digital hemodynamic data, a pluralityof health parameters; and determine a hypotension probability index(HPI) representing a probability of a future hypotension event for thepatient based on the plurality of health parameters, and execute thegraphical user interface to: provide a selection screen on the displayenabling a user to select a plurality of parameters for viewing on thedisplay from among health parameters of the patient being tracked by thesystem and being stored in the system memory; overlay an alarm screen asa pop-up on the display in response to the HPI of the patient satisfyinga predetermined risk criterion; and provide an HPI diagnostic screenshowing values for one or more of the plurality of health parameters. 2.The health monitoring unit of claim 1, wherein the hardware processorcauses the alarm screen to be persistently displayed until an input isreceived from the user via the graphical user interface.
 3. The healthmonitoring unit of claim 1, wherein the main screen shows the HPI as afunction of time.
 4. The health monitoring unit of claim 1, wherein thegraphical user interface displays graphical control elements that enablethe user to access the HPI diagnostic screen from the main screen andthe alarm screen.
 5. The health monitoring unit of claim 1, wherein theHPI diagnostic screen displays predictive health parameters to assistthe user in identifying a most probable cause of the future hypotensionevent.
 6. The health monitoring unit of claim 1, wherein the HPIdiagnostic screen displays predictive health parameters to assist theuser in determining a medical intervention for preventing the futurehypotension event.
 7. The health monitoring unit of claim 1, wherein aplurality of predicative health parameters including mean arterialpressure (MAP), cardiac output (CO), systemic vascular resistance (SVR),pulse rate (PR), stroke volume (SV), stroke volume variation (SVV), leftventricle contractility (dP/dt), and arterial elastance (E_(a)) aredrawn on the HPI diagnostic screen as a tree with MAP at the top, withCO and SVR linked to one another below MAP by a branched connectioncoming from MAP, with PR and SV linked to one another below CO by abranched connection coming from CO, and with SVV, dP/dt, and E_(a)linked to one another below SV by a branched connection coming from SV.8. The system of claim 1, wherein the graphical user interface includesa selection module that provides the selection screen on the display, apresentation module that presents the main screen on the display, anoverlay module that overlays the alarm screen as a pop-up on thedisplay, and a user access module that provides the HPI diagnosticscreen on the display.
 9. The system of claim 1, wherein the displaycomprises a touch screen user interface.
 10. The system of claim 1,wherein the plurality of parameters presented by the selection screeninclude cardiac output, stroke volume, stroke volume variation,diastolic pressure, pulse rate, stroke volume index, systemic vascularresistance, mean arterial pressure, and hypotension probability index.11. The system of claim 10, wherein the plurality of parameterspresented by the selection screen further include systemic vascularresistance index, cardiac index, and systolic pressure.
 12. The systemof claim 1, wherein the main screen includes a numerical representationof the HPI.
 13. The system of claim 12, wherein the numericalrepresentation of the HPI is a number between zero and one hundred. 14.The system of claim 1, wherein the alarm screen includes a numericalrepresentation of the HPI.
 15. The system of claim 1, wherein the HPIdiagnostic screen includes a numerical representation of the HPI. 16.The system of claim 1, wherein once the alarm screen is overlaid as apop-up on the display, the alarm screen overlays the displaypersistently until an acknowledgement input is provided via thegraphical user interface.
 17. The system of claim 16, wherein the alarmscreen includes an acknowledgement bar that is selectable to produce theacknowledgement input.
 18. The system of claim 17, wherein the alarmscreen includes an information bar that is selectable to allow access tothe HPI diagnostic screen.
 19. The system of claim 1, wherein the HPIdiagnostic screen is accessible from the main screen via a shortcutbutton.
 20. The system of claim 1, wherein overlaying the alarm screenas a pop-up causes a sensory alarm to be invoked by the hardwareprocessor.
 21. The system of claim 20, wherein the sensory alarm is avisual alarm that is invoked as flashing or colored graphics shown bythe graphical user interface on the display.
 22. The system of claim 20,wherein the sensory alarm is an audible alarm.
 23. The system of claim20, wherein the sensor alarm is a haptic alarm.
 24. The system of claim1, wherein the hardware processor is configured to cause the alarmscreen to pop-up immediately when the HPI satisfies a first riskcriterion.
 25. The system of claim 24, wherein the hardware processor isconfigured to cause the alarm screen to pop-up when the HPI satisfies asecond risk criterion continuously for a first predetermined timeperiod.
 26. The system of claim 25, wherein the hardware processor isconfigured to cause the alarm screen to pop-up when the HPI satisfies athird risk criterion continuously for a second, longer, predeterminedtime period.
 27. The system of claim 24, wherein the hardware processoris configured to cause the alarm screen to pop-up when the HPI satisfiesa fourth risk criterion a predetermined number of times over apredetermined time interval.